(Bloomberg) -- Texas Governor Greg Abbott ordered residents to wear face coverings in public amid a spike in Covid-19 cases across the second-most populous U.S. state.

In a reversal of his months-long opposition to such a mandate, Abbott on Thursday said the order applies to all counties with 20 or more virus cases. He also barred people from gathering outdoors in groups larger than 10.

The Republican governor has been under growing pressure from Democratic mayors and county leaders to crack down or at least grant them authority to mandate masks and other restrictions. As he moved to aggressively reopen the state’s economy in recent weeks, Abbott overruled local efforts to enforce stay-home orders and similar restrictions.

“We have the ability to keep businesses open and move our economy forward so that Texans can continue to earn a paycheck, but it requires each of us to do our part to protect one another—and that means wearing a face covering in public spaces,” Abbott said in a statement.

Abbott has been scaling back his reopening as virus cases exploded and the sickest patients began to overwhelm intensive-care wards in Houston and elsewhere. It’s unclear how the order will impact the state Republican Party’s planned July 16-18 convention in Houston.

“We have a limited window in which to regain control,” Houston Mayor Sylvester Turner said during a media briefing moments before Abbott issued his order. A mask order would help “defuel this virus.”

(Updates with governor’s remarks in fourth paragraph.)

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